usb: musb: kill global and static for multi instance

Moved global variable "musb_debugfs_root" and static variable
"old_state" to 'struct musb' to help support multi instance of
musb controller as present on AM335x platform.

Also removed the global variable "orig_dma_mask" and filled the
dev->dma_mask with parent device's dma_mask.

Signed-off-by: Ajay Kumar Gupta <ajay.gupta@ti.com>
Signed-off-by: Santhapuri, Damodar <damodar.santhapuri@ti.com>
Signed-off-by: Ravi Babu <ravibabu@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/musb/musb_debugfs.c b/drivers/usb/musb/musb_debugfs.c
index 40a37c9..1d6e8af 100644
--- a/drivers/usb/musb/musb_debugfs.c
+++ b/drivers/usb/musb/musb_debugfs.c
@@ -103,8 +103,6 @@
 	{  }	/* Terminating Entry */
 };
 
-static struct dentry *musb_debugfs_root;
-
 static int musb_regdump_show(struct seq_file *s, void *unused)
 {
 	struct musb		*musb = s->private;
@@ -241,7 +239,7 @@
 	struct dentry		*file;
 	int			ret;
 
-	root = debugfs_create_dir("musb", NULL);
+	root = debugfs_create_dir(dev_name(musb->controller), NULL);
 	if (!root) {
 		ret = -ENOMEM;
 		goto err0;
@@ -261,7 +259,7 @@
 		goto err1;
 	}
 
-	musb_debugfs_root = root;
+	musb->debugfs_root = root;
 
 	return 0;
 
@@ -274,5 +272,5 @@
 
 void /* __init_or_exit */ musb_exit_debugfs(struct musb *musb)
 {
-	debugfs_remove_recursive(musb_debugfs_root);
+	debugfs_remove_recursive(musb->debugfs_root);
 }